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The expression of the laminin-binding protein (LBP) on cellular membranes in different cell lines has been studied. A high level of replication of Venezuelan equine encephalomyelitis (VEE) virus was registered in Vero cells with high levels of LBP on the cell surface. The treatment of Vero cells with monoclonal antibodies to human LBP reduced VEE virus replication by a factor of more than 200. A low level of LBP expression on the surface of 293 cells was increased via transfection by plasmid with gene for human LBP. The VEE virus replication in transfected cells (9S2) was increased by more that 2000 times compared to the 293 cells. The results demonstrated the principal role of cellular LBP in the entry of VEE virus into mammalian cells. It is proposed that LBP is a key cellular protein for the early stage of the VEE virus replication in cells. LBP may be a target protein for the development of a new generation of antiviral drugs capable of inhibiting (enhancing) the alphavirus replication in human cells.  相似文献   
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A new genus of praying mantis is described, Chlorocalis n. gen., with two species, C. maternaschulzei n. sp. and C. prasina n. sp. from the Greater Mekong Region. Chlorocalis is placed in Mantidae and can be immediately recognized by the presence of dark brown (male) or yellow-whitish (female) oblique stripes on the forewings, a large conical bulge on the clypeus, two large conical bulges on either side of the inferior margin of the lower frons, and the male genitalia with two distal processes on the ventral phallomere. Chlorocalis maternaschulzei is a widespread lowland species with records as west as Nakhon Ratchasima Province, Thailand, and as east as mount Núi Chúa in southern Central Vietnam. We consider this species to be of Least Concern. In contrast, C. prasina is a narrow-range mountain endemic of the Vietnamese Central Highlands in the Annamite range and is assessed by us to be Vulnerable. The new findings demonstrate the still very poor knowledge on praying mantis species diversity in South-East Asia and the urgency to resolve this taxonomic deficiency in the face of biodiversity loss.  相似文献   
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Origins of Life and Evolution of Biospheres - Syntheses under shock in nitrogen bubbled samples of the water – formamide – bicarbonate – sodium hydroxide system at...  相似文献   
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The influence of sinusoidal 45-Hz magnetic fields on the brain functions of 20 volunteers was investigated in a double-blind study using spectral analysis of EEG and measurements of Omega potentials and reaction time (RT). The field strength was 1,000 A/m (1.26 mT) and the duration of exposure was 1 h. Ten volunteers were exposed to a continuous field and ten received an intermittent exposure (1 s on/1 s off). Each person received one real and one sham exposure. One half of the volunteers got the real exposure first and the sham treatment after at least 24 h. For the rest, the sequence was inverse. The measurements of EEG, omega potentials and RT were performed before and after each exposure. Several statistically significant changes were observed, most of them after intermittent exposure. In the EEG, an increase of alpha (7.6–13.9 Hz) activity and a decrease of delta (1.5–3.9 Hz) activity were observed. β waves (14.2–20 Hz) increased in the frontal derivations as did the total power in occipital derivations. The mean and peak frequencies of EEG increased mainly in the frontal derivations. No direct effects on RT were seen. Learning to perform the RT test (decrease of RT in repeated trials), however, seemed to be affected by the exposure. The persons who received real exposure first learned more slowly than those who got sham exposure first. Further experiments are necessary to confirm the findings and for understanding the mechanisms of the effects. © 1993 Wiley-Liss. Inc.  相似文献   
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New isoforms of apolipoprotein (apo)C-I and apoC-III have been detected in delipidated fractions from very low density lipoprotein (VLDL) using matrix-assisted laser desorption (MALDI) and electrospray ionization (ESI) mass spectrometry (MS). The cleavage sites of truncated apoC-III isoforms have also been identified. The VLDL fractions were isolated by fixed-angle single-spin ultracentrifugation using a self-generating sucrose density gradient and delipidated using a newly developed C18 solid phase extraction protocol. Fifteen apoC isoforms and apoE were identified in the MALDI spectra and the existence of the more abundant species was verified by ESI-MS. The relative intensities of the apoCs are closely correlated in three normolipidemic subjects. A fourth subject with type V hyperlipidemia exhibited an elevated apoC-III level and a suppressed level of the newly discovered truncated apoC-I isoform. ApoC-II was found to be particularly sensitive to in vitro oxidation. The dynamic range and specificity of the MALDI assay shows that the complete apoC isoform profile and apoE phenotype can be obtained in a single measurement from the delipidated VLDL fraction.  相似文献   
48.
The cerebral free radical oxidation processes on 40 Wistar rats-males were studied by evaluation of thiobarbituric-active products of lipid peroxidation level, superoxide dismutase and glutathione peroxidase activity in sensomotor cortex, hypothalamus and brain stem. Was found that differential stability of rats to motor activities during single intensive physical loading is due by reactivity of free radicals oxidation, associated with decrease of cerebral antioxidant enzymes activity. Long term intensive physical loading may accompanied by reducing of reserve possibilities of antioxidant enzymes an cerebral structures, what possible play potential role in pathogenetic mechanisms of osteoarthritis.  相似文献   
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Free radical mechanism of the cold stress development in rats   总被引:5,自引:0,他引:5  
Development of cold stress in rats is characterized by sharp activation of lipid peroxidation accompanied by a considerable increase of the diene conjugates level and Schiff bases in tissues of brain, liver and in erythrocytes. There is a shift in the prooxidant--antioxidant balance of the organism in the form of amplification of xanthine oxidase prooxidant enzymatic activity in the brain and liver, and a decrease of myeloperoxidase activity in blood neutrophiles of rats. The attrition at cold stress, mainly, of enzymatic endocellular antioxidant system as the result of inhibition of superoxide dismutase, catalase, glutathione reductase activities in brain, liver and erythrocytes is indemnified by activation of non-enzymatic antioxidant mechanisms. In conditions of cold stress, destabilization of erythrocyte membranes of rats described by a decrease of the microviscosity of protein-lipid contact zones and reduction of degree of immersing of proteins in lipid membrane owing to exhibiting proteins from the hydrophobic zone of membranes, or their aggregate, increase of polarity of lipid phase and negative surface charge, is marked.  相似文献   
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